Various devices, generally known as pessaries, are utilized for the treatment of prolapse of internal female organs, including the organs of the digestive tract and sex organs. Increased age is a risk factor for women for uterine or other prolapse. The use of pessaries is indicated where the correction of prolapse by surgery is inadvisable, as for example where a woman is in generally poor physical condition, or where she is of advanced age.
The first known pessaries are believed to have been small oranges, and may have been in use since 2,000 years ago. Modem literature describing pessaries dates back to a period prior to the 1850's. More recent patents of interest and relating to pessaries include U.S. Pat. Nos. 4,031,886, 4,307,716, 4,516,570, 4,579,110, 4,607,630, 4,724,832, 4,823,814, 5,014,722, 5,224,494, and 5,224,495. The pessaries shown in these patents and otherwise known in the prior art can be of many shapes, including ring shaped, spherical, horseshoe, helical, cylindrical, and ovoid, among others. The inner part of the pessary generally includes a structural support. Such a support may be mechanical, such as a metal frame, or pneumatic, i.e., air supported. The outside surface of the pessary is generally made of an inert, biocompatible material, such as rubber or silicone. A pessary of the horseshoe type is known as a "Gehrung" pessary. One example of such a "Gehrung" pessary is shown at page 14 of a catalog by Milex Products, Incorporated, the assignee of the present application.
The prior art "Gehrung" pessaries provide generally effective support in cases of cystocele and rectocele. The solid metal frame of these prior art devices permits these devices to be bent somewhat into a new shape more precisely meeting the needs of a particular patient. In addition, a lesser flexing of the frame, to an extent that does not permanently change the shape of the device, facilitates insertion.
After insertion into the patient, the shape of these devices does not change, but remains identical to that shape into which it the supporting frame was bent, i.e., the shape just prior to insertion. This tendency to resist changes in shape is generally advantageous for some patients, particularly those patients whose anatomy or general physical conditions do not worsen over time.
However, for those patients whose condition does worsen over time, the convention "Gehrung" pessary may not be ideal. When internal organs undergo further shifts, additional weight and pressure may be placed onto the pessary. As a result of this increased pressure, the pessary may shift within the uterus of the patient. These shifts may in turn increase the pressure on the uterine walls upon which the pessary rests. As a result, a pessary which was comfortable when initially fitted may, at a later time, become uncomfortable for the patient.